Archive for the ‘Hacking’ Category

These guys appear to have put a quite an amount of research into this subject and attack vector. However I’m disappointed about how little research and citations of prior work they seem to have included, even if it is not based around USB devices it is still relevant. Then there is the ‘case’ of the 3rd party publicly available code to reprogram the SAME USB device released BEFORE their presentation.

There is lots of cool scrap available on Ebay, specifically items from video processing companies/telecom companies that sold their scrap to clowns who were supposed to ‘destroy it’ ( you know the ones, who advertise ‘secure destruction’ of equipment). All you need is a JTAG pod, frequency generator (NE555), multi-tester and a little bit of time.

Background Back In Jan I threw together a library for reading Nand-flash chips on the Arduino, part of the reason for this was to try to throw together a simple and highly cost-effective way to read Nand-flash chips.

It was not until the start of this year (2013) that there has been such a long run of exponential increases in the bitcoin difficulty. Current difficulty is 26162876 with a PPS share rate of 0.00000092 BTC (actually it is lower once you consider fees etc)

After mining for a few years using various systems- CPU, GPU, FPGA.. The time has now come to reconsider the situation…. B.F.L have continually failed to deliver what they promised they were experts in…. Power consumption does not match,shipping does not match, quality does not match. Back in January, they were saying delivery would be in Two months, they are still claiming that all back orders would be cleared before end of September 2013, personally I find this unlikely since they STILL have not shipped any of my orders, and for them to clear the backlog, they should at least have my orders in ‘production'(I’m in the top quarter of their estimated order book). Plus the number of people who have had new ASIC kit only for it to fail abysmally is rapidly increasing.. I have decided to give them until the middle of August and then I’m pulling the plug on the orders.

The boards are a little long making programming via JTAG difficult, not to mention the 14 Pin IDC connector is not really suitable for a standard 14 pin IDC plug (a fact I discovered AFTER I returned from China with a bag full of parts).

As we can see it is a little cramped by the JTAG connector (directly inline with a fan), yep I can say officially that even a 12 Volt fan is capable of doing serious damage to finger tips and finger nails.

Caveats

There were a number of issues with the FORA(For-a) video processing boards.

After digging about we find that the FPGA core voltage has been fixed at 0.97v This is a little low for proper mining

We had to strip out an additional component that supported the PCI bus as the part was running from the 3V3 supply. Failure to remove it would be driving the chip at 170% of its rating thereby forcing it to dump several hundred mA as heat…

Yep We had an Idea that there was something shitty about the power-supply setup… The Bellinix modules used are ‘programmable’ via an external sense resistor, problem was that when we replaced the sense resistor NOTHING happened to the supply voltage, in fact completely removing the sense resistor also had no effect. * UPDATE 29Th June 2013, we finally tracked this down to a defective Bellinix module… We can now adjust the core voltage for the FPGA via a system that reprograms the DC/DC PSU module.